What is different between devnet and testnet?

[banool]

Originally from Stack Overflow.

I'm starting to build a dapp on Aptos and I notice that there are two development networks, devnet and testnet. What are the differences between these two?

[banool]

Release cadence

Devnet is generally released every week. Testnet is generally released every two weeks, after devnet.

This means devnet gets new features sooner and more frequently.

Persistence

With devnet, the chain is reset every release. All data is wiped, including any deployed modules, accounts, etc. and the chain restarts from genesis with a new chain ID. If you're building on devnet this means you must redeploy your Move modules and accounts every week.

Testnet is never wiped, similar to mainnet.

Which should you use?

Generally speaking testnet is a friendlier developer experience because you don't need to keep redeploying your code / recreating accounts. If you want access to new features as fast as possible or you're doing stuff you want to be wiped, devnet might be a good choice.